Re: [PATCH v6 1/3] of/pci: Unify pci_process_bridge_OF_ranges fromMicroblaze and PowerPC

From: Michal Simek
Date: Mon Apr 15 2013 - 12:51:20 EST


Hi Thomas and Andrew,

First of all I would recommend you to add your tree to 0-day testing
system where you can easily catch up compilation failures for
microblaze and others.

Getting this compilation failure:
drivers/of/of_pci.c: In function 'pci_process_bridge_OF_ranges':
drivers/of/of_pci.c:88:22: error: storage size of 'range' isn't known
drivers/of/of_pci.c:89:29: error: storage size of 'parser' isn't known
drivers/of/of_pci.c:96:2: error: implicit declaration of function 'of_pci_range_parser' [-Werror=implicit-function-declaration]
drivers/of/of_pci.c:100:2: error: implicit declaration of function 'for_each_of_pci_range' [-Werror=implicit-function-declaration]
drivers/of/of_pci.c:100:41: error: expected ';' before '{' token
drivers/of/of_pci.c:90:6: warning: unused variable 'res_type' [-Wunused-variable]
drivers/of/of_pci.c:89:29: warning: unused variable 'parser' [-Wunused-variable]
drivers/of/of_pci.c:88:22: warning: unused variable 'range' [-Wunused-variable]
drivers/of/of_pci.c:87:19: warning: unused variable 'res' [-Wunused-variable]
drivers/of/of_pci.c:86:21: warning: unused variable 'isa_mb' [-Wunused-variable]
drivers/of/of_pci.c:85:17: warning: unused variable 'isa_hole' [-Wunused-variable]
drivers/of/of_pci.c:85:6: warning: unused variable 'memno' [-Wunused-variable]

which is caused missing linux/of_addresss.h in of_pci.c.
PowerPC probably won't have this problem because you have this header in asm/prom.h
but based on the same comment it is better to add it directly to the files.

That's why please add this header to this patch.

diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index 3e428a1..f30887e 100644
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -1,6 +1,7 @@
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/of.h>
+#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <asm/prom.h>


When you fix it:
Acked-by: Michal Simek <monstr@xxxxxxxxx>

Thanks,
Michal



On 04/15/2013 02:57 PM, Thomas Petazzoni wrote:
> Michal, Ben,
>
> Would you have some time to look at this patch and give your comments
> and/or ACK ? Since it touches the PowerPC and Microblaze core code, we
> need your agreement to merge this code, and quite a bit of code pending
> for 3.10 depends on this patch.
>
> Rob, alternatively, could we imagine doing a different version of the
> 'of/pci: Provide support for parsing PCI DT ranges property' that
> introduces the new API only, leaving the PowerPC and Microblaze rework
> as follow-up efforts, so that all the PCIe drivers that depend on this
> patch can get in for 3.10 ? I'd find it pretty sad if the Marvell PCIe
> driver that has been worked on since 4+ months does not get into 3.10
> just because this patch cannot be merged.
>
> Thanks!
>
> Thomas
>
> On Thu, 11 Apr 2013 16:26:07 +0100, Andrew Murray wrote:
>> The pci_process_bridge_OF_ranges function, used to parse the "ranges"
>> property of a PCI host device, is found in both Microblaze and PowerPC
>> architectures. These implementations are nearly identical. This patch
>> moves this common code to a common place.
>>
>> Signed-off-by: Andrew Murray <Andrew.Murray@xxxxxxx>
>> Signed-off-by: Liviu Dudau <Liviu.Dudau@xxxxxxx>
>> Reviewed-by: Rob Herring <rob.herring@xxxxxxxxxxx>
>> Tested-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
>> ---
>> arch/microblaze/include/asm/pci-bridge.h | 5 +-
>> arch/microblaze/pci/pci-common.c | 192 ----------------------------
>> arch/powerpc/include/asm/pci-bridge.h | 5 +-
>> arch/powerpc/kernel/pci-common.c | 192 ----------------------------
>> drivers/of/of_pci.c | 200 ++++++++++++++++++++++++++++++
>> include/linux/of_pci.h | 4 +
>> 6 files changed, 206 insertions(+), 392 deletions(-)
>>
>> diff --git a/arch/microblaze/include/asm/pci-bridge.h b/arch/microblaze/include/asm/pci-bridge.h
>> index cb5d397..5783cd6 100644
>> --- a/arch/microblaze/include/asm/pci-bridge.h
>> +++ b/arch/microblaze/include/asm/pci-bridge.h
>> @@ -10,6 +10,7 @@
>> #include <linux/pci.h>
>> #include <linux/list.h>
>> #include <linux/ioport.h>
>> +#include <linux/of_pci.h>
>>
>> struct device_node;
>>
>> @@ -132,10 +133,6 @@ extern void setup_indirect_pci(struct pci_controller *hose,
>> extern struct pci_controller *pci_find_hose_for_OF_device(
>> struct device_node *node);
>>
>> -/* Fill up host controller resources from the OF node */
>> -extern void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> - struct device_node *dev, int primary);
>> -
>> /* Allocate & free a PCI host bridge structure */
>> extern struct pci_controller *pcibios_alloc_controller(struct device_node *dev);
>> extern void pcibios_free_controller(struct pci_controller *phb);
>> diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
>> index 9ea521e..2735ad9 100644
>> --- a/arch/microblaze/pci/pci-common.c
>> +++ b/arch/microblaze/pci/pci-common.c
>> @@ -622,198 +622,6 @@ void pci_resource_to_user(const struct pci_dev *dev, int bar,
>> *end = rsrc->end - offset;
>> }
>>
>> -/**
>> - * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
>> - * @hose: newly allocated pci_controller to be setup
>> - * @dev: device node of the host bridge
>> - * @primary: set if primary bus (32 bits only, soon to be deprecated)
>> - *
>> - * This function will parse the "ranges" property of a PCI host bridge device
>> - * node and setup the resource mapping of a pci controller based on its
>> - * content.
>> - *
>> - * Life would be boring if it wasn't for a few issues that we have to deal
>> - * with here:
>> - *
>> - * - We can only cope with one IO space range and up to 3 Memory space
>> - * ranges. However, some machines (thanks Apple !) tend to split their
>> - * space into lots of small contiguous ranges. So we have to coalesce.
>> - *
>> - * - We can only cope with all memory ranges having the same offset
>> - * between CPU addresses and PCI addresses. Unfortunately, some bridges
>> - * are setup for a large 1:1 mapping along with a small "window" which
>> - * maps PCI address 0 to some arbitrary high address of the CPU space in
>> - * order to give access to the ISA memory hole.
>> - * The way out of here that I've chosen for now is to always set the
>> - * offset based on the first resource found, then override it if we
>> - * have a different offset and the previous was set by an ISA hole.
>> - *
>> - * - Some busses have IO space not starting at 0, which causes trouble with
>> - * the way we do our IO resource renumbering. The code somewhat deals with
>> - * it for 64 bits but I would expect problems on 32 bits.
>> - *
>> - * - Some 32 bits platforms such as 4xx can have physical space larger than
>> - * 32 bits so we need to use 64 bits values for the parsing
>> - */
>> -void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> - struct device_node *dev, int primary)
>> -{
>> - const u32 *ranges;
>> - int rlen;
>> - int pna = of_n_addr_cells(dev);
>> - int np = pna + 5;
>> - int memno = 0, isa_hole = -1;
>> - u32 pci_space;
>> - unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
>> - unsigned long long isa_mb = 0;
>> - struct resource *res;
>> -
>> - pr_info("PCI host bridge %s %s ranges:\n",
>> - dev->full_name, primary ? "(primary)" : "");
>> -
>> - /* Get ranges property */
>> - ranges = of_get_property(dev, "ranges", &rlen);
>> - if (ranges == NULL)
>> - return;
>> -
>> - /* Parse it */
>> - pr_debug("Parsing ranges property...\n");
>> - while ((rlen -= np * 4) >= 0) {
>> - /* Read next ranges element */
>> - pci_space = ranges[0];
>> - pci_addr = of_read_number(ranges + 1, 2);
>> - cpu_addr = of_translate_address(dev, ranges + 3);
>> - size = of_read_number(ranges + pna + 3, 2);
>> -
>> - pr_debug("pci_space: 0x%08x pci_addr:0x%016llx ",
>> - pci_space, pci_addr);
>> - pr_debug("cpu_addr:0x%016llx size:0x%016llx\n",
>> - cpu_addr, size);
>> -
>> - ranges += np;
>> -
>> - /* If we failed translation or got a zero-sized region
>> - * (some FW try to feed us with non sensical zero sized regions
>> - * such as power3 which look like some kind of attempt
>> - * at exposing the VGA memory hole)
>> - */
>> - if (cpu_addr == OF_BAD_ADDR || size == 0)
>> - continue;
>> -
>> - /* Now consume following elements while they are contiguous */
>> - for (; rlen >= np * sizeof(u32);
>> - ranges += np, rlen -= np * 4) {
>> - if (ranges[0] != pci_space)
>> - break;
>> - pci_next = of_read_number(ranges + 1, 2);
>> - cpu_next = of_translate_address(dev, ranges + 3);
>> - if (pci_next != pci_addr + size ||
>> - cpu_next != cpu_addr + size)
>> - break;
>> - size += of_read_number(ranges + pna + 3, 2);
>> - }
>> -
>> - /* Act based on address space type */
>> - res = NULL;
>> - switch ((pci_space >> 24) & 0x3) {
>> - case 1: /* PCI IO space */
>> - pr_info(" IO 0x%016llx..0x%016llx -> 0x%016llx\n",
>> - cpu_addr, cpu_addr + size - 1, pci_addr);
>> -
>> - /* We support only one IO range */
>> - if (hose->pci_io_size) {
>> - pr_info(" \\--> Skipped (too many) !\n");
>> - continue;
>> - }
>> - /* On 32 bits, limit I/O space to 16MB */
>> - if (size > 0x01000000)
>> - size = 0x01000000;
>> -
>> - /* 32 bits needs to map IOs here */
>> - hose->io_base_virt = ioremap(cpu_addr, size);
>> -
>> - /* Expect trouble if pci_addr is not 0 */
>> - if (primary)
>> - isa_io_base =
>> - (unsigned long)hose->io_base_virt;
>> - /* pci_io_size and io_base_phys always represent IO
>> - * space starting at 0 so we factor in pci_addr
>> - */
>> - hose->pci_io_size = pci_addr + size;
>> - hose->io_base_phys = cpu_addr - pci_addr;
>> -
>> - /* Build resource */
>> - res = &hose->io_resource;
>> - res->flags = IORESOURCE_IO;
>> - res->start = pci_addr;
>> - break;
>> - case 2: /* PCI Memory space */
>> - case 3: /* PCI 64 bits Memory space */
>> - pr_info(" MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
>> - cpu_addr, cpu_addr + size - 1, pci_addr,
>> - (pci_space & 0x40000000) ? "Prefetch" : "");
>> -
>> - /* We support only 3 memory ranges */
>> - if (memno >= 3) {
>> - pr_info(" \\--> Skipped (too many) !\n");
>> - continue;
>> - }
>> - /* Handles ISA memory hole space here */
>> - if (pci_addr == 0) {
>> - isa_mb = cpu_addr;
>> - isa_hole = memno;
>> - if (primary || isa_mem_base == 0)
>> - isa_mem_base = cpu_addr;
>> - hose->isa_mem_phys = cpu_addr;
>> - hose->isa_mem_size = size;
>> - }
>> -
>> - /* We get the PCI/Mem offset from the first range or
>> - * the, current one if the offset came from an ISA
>> - * hole. If they don't match, bugger.
>> - */
>> - if (memno == 0 ||
>> - (isa_hole >= 0 && pci_addr != 0 &&
>> - hose->pci_mem_offset == isa_mb))
>> - hose->pci_mem_offset = cpu_addr - pci_addr;
>> - else if (pci_addr != 0 &&
>> - hose->pci_mem_offset != cpu_addr - pci_addr) {
>> - pr_info(" \\--> Skipped (offset mismatch) !\n");
>> - continue;
>> - }
>> -
>> - /* Build resource */
>> - res = &hose->mem_resources[memno++];
>> - res->flags = IORESOURCE_MEM;
>> - if (pci_space & 0x40000000)
>> - res->flags |= IORESOURCE_PREFETCH;
>> - res->start = cpu_addr;
>> - break;
>> - }
>> - if (res != NULL) {
>> - res->name = dev->full_name;
>> - res->end = res->start + size - 1;
>> - res->parent = NULL;
>> - res->sibling = NULL;
>> - res->child = NULL;
>> - }
>> - }
>> -
>> - /* If there's an ISA hole and the pci_mem_offset is -not- matching
>> - * the ISA hole offset, then we need to remove the ISA hole from
>> - * the resource list for that brige
>> - */
>> - if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
>> - unsigned int next = isa_hole + 1;
>> - pr_info(" Removing ISA hole at 0x%016llx\n", isa_mb);
>> - if (next < memno)
>> - memmove(&hose->mem_resources[isa_hole],
>> - &hose->mem_resources[next],
>> - sizeof(struct resource) * (memno - next));
>> - hose->mem_resources[--memno].flags = 0;
>> - }
>> -}
>> -
>> /* Decide whether to display the domain number in /proc */
>> int pci_proc_domain(struct pci_bus *bus)
>> {
>> diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h
>> index 025a130..205bfba 100644
>> --- a/arch/powerpc/include/asm/pci-bridge.h
>> +++ b/arch/powerpc/include/asm/pci-bridge.h
>> @@ -10,6 +10,7 @@
>> #include <linux/pci.h>
>> #include <linux/list.h>
>> #include <linux/ioport.h>
>> +#include <linux/of_pci.h>
>> #include <asm-generic/pci-bridge.h>
>>
>> struct device_node;
>> @@ -231,10 +232,6 @@ extern int pcibios_map_io_space(struct pci_bus *bus);
>> extern struct pci_controller *pci_find_hose_for_OF_device(
>> struct device_node* node);
>>
>> -/* Fill up host controller resources from the OF node */
>> -extern void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> - struct device_node *dev, int primary);
>> -
>> /* Allocate & free a PCI host bridge structure */
>> extern struct pci_controller *pcibios_alloc_controller(struct device_node *dev);
>> extern void pcibios_free_controller(struct pci_controller *phb);
>> diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
>> index fa12ae4..6edf396 100644
>> --- a/arch/powerpc/kernel/pci-common.c
>> +++ b/arch/powerpc/kernel/pci-common.c
>> @@ -640,198 +640,6 @@ void pci_resource_to_user(const struct pci_dev *dev, int bar,
>> *end = rsrc->end - offset;
>> }
>>
>> -/**
>> - * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
>> - * @hose: newly allocated pci_controller to be setup
>> - * @dev: device node of the host bridge
>> - * @primary: set if primary bus (32 bits only, soon to be deprecated)
>> - *
>> - * This function will parse the "ranges" property of a PCI host bridge device
>> - * node and setup the resource mapping of a pci controller based on its
>> - * content.
>> - *
>> - * Life would be boring if it wasn't for a few issues that we have to deal
>> - * with here:
>> - *
>> - * - We can only cope with one IO space range and up to 3 Memory space
>> - * ranges. However, some machines (thanks Apple !) tend to split their
>> - * space into lots of small contiguous ranges. So we have to coalesce.
>> - *
>> - * - We can only cope with all memory ranges having the same offset
>> - * between CPU addresses and PCI addresses. Unfortunately, some bridges
>> - * are setup for a large 1:1 mapping along with a small "window" which
>> - * maps PCI address 0 to some arbitrary high address of the CPU space in
>> - * order to give access to the ISA memory hole.
>> - * The way out of here that I've chosen for now is to always set the
>> - * offset based on the first resource found, then override it if we
>> - * have a different offset and the previous was set by an ISA hole.
>> - *
>> - * - Some busses have IO space not starting at 0, which causes trouble with
>> - * the way we do our IO resource renumbering. The code somewhat deals with
>> - * it for 64 bits but I would expect problems on 32 bits.
>> - *
>> - * - Some 32 bits platforms such as 4xx can have physical space larger than
>> - * 32 bits so we need to use 64 bits values for the parsing
>> - */
>> -void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> - struct device_node *dev, int primary)
>> -{
>> - const u32 *ranges;
>> - int rlen;
>> - int pna = of_n_addr_cells(dev);
>> - int np = pna + 5;
>> - int memno = 0, isa_hole = -1;
>> - u32 pci_space;
>> - unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
>> - unsigned long long isa_mb = 0;
>> - struct resource *res;
>> -
>> - printk(KERN_INFO "PCI host bridge %s %s ranges:\n",
>> - dev->full_name, primary ? "(primary)" : "");
>> -
>> - /* Get ranges property */
>> - ranges = of_get_property(dev, "ranges", &rlen);
>> - if (ranges == NULL)
>> - return;
>> -
>> - /* Parse it */
>> - while ((rlen -= np * 4) >= 0) {
>> - /* Read next ranges element */
>> - pci_space = ranges[0];
>> - pci_addr = of_read_number(ranges + 1, 2);
>> - cpu_addr = of_translate_address(dev, ranges + 3);
>> - size = of_read_number(ranges + pna + 3, 2);
>> - ranges += np;
>> -
>> - /* If we failed translation or got a zero-sized region
>> - * (some FW try to feed us with non sensical zero sized regions
>> - * such as power3 which look like some kind of attempt at exposing
>> - * the VGA memory hole)
>> - */
>> - if (cpu_addr == OF_BAD_ADDR || size == 0)
>> - continue;
>> -
>> - /* Now consume following elements while they are contiguous */
>> - for (; rlen >= np * sizeof(u32);
>> - ranges += np, rlen -= np * 4) {
>> - if (ranges[0] != pci_space)
>> - break;
>> - pci_next = of_read_number(ranges + 1, 2);
>> - cpu_next = of_translate_address(dev, ranges + 3);
>> - if (pci_next != pci_addr + size ||
>> - cpu_next != cpu_addr + size)
>> - break;
>> - size += of_read_number(ranges + pna + 3, 2);
>> - }
>> -
>> - /* Act based on address space type */
>> - res = NULL;
>> - switch ((pci_space >> 24) & 0x3) {
>> - case 1: /* PCI IO space */
>> - printk(KERN_INFO
>> - " IO 0x%016llx..0x%016llx -> 0x%016llx\n",
>> - cpu_addr, cpu_addr + size - 1, pci_addr);
>> -
>> - /* We support only one IO range */
>> - if (hose->pci_io_size) {
>> - printk(KERN_INFO
>> - " \\--> Skipped (too many) !\n");
>> - continue;
>> - }
>> -#ifdef CONFIG_PPC32
>> - /* On 32 bits, limit I/O space to 16MB */
>> - if (size > 0x01000000)
>> - size = 0x01000000;
>> -
>> - /* 32 bits needs to map IOs here */
>> - hose->io_base_virt = ioremap(cpu_addr, size);
>> -
>> - /* Expect trouble if pci_addr is not 0 */
>> - if (primary)
>> - isa_io_base =
>> - (unsigned long)hose->io_base_virt;
>> -#endif /* CONFIG_PPC32 */
>> - /* pci_io_size and io_base_phys always represent IO
>> - * space starting at 0 so we factor in pci_addr
>> - */
>> - hose->pci_io_size = pci_addr + size;
>> - hose->io_base_phys = cpu_addr - pci_addr;
>> -
>> - /* Build resource */
>> - res = &hose->io_resource;
>> - res->flags = IORESOURCE_IO;
>> - res->start = pci_addr;
>> - break;
>> - case 2: /* PCI Memory space */
>> - case 3: /* PCI 64 bits Memory space */
>> - printk(KERN_INFO
>> - " MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
>> - cpu_addr, cpu_addr + size - 1, pci_addr,
>> - (pci_space & 0x40000000) ? "Prefetch" : "");
>> -
>> - /* We support only 3 memory ranges */
>> - if (memno >= 3) {
>> - printk(KERN_INFO
>> - " \\--> Skipped (too many) !\n");
>> - continue;
>> - }
>> - /* Handles ISA memory hole space here */
>> - if (pci_addr == 0) {
>> - isa_mb = cpu_addr;
>> - isa_hole = memno;
>> - if (primary || isa_mem_base == 0)
>> - isa_mem_base = cpu_addr;
>> - hose->isa_mem_phys = cpu_addr;
>> - hose->isa_mem_size = size;
>> - }
>> -
>> - /* We get the PCI/Mem offset from the first range or
>> - * the, current one if the offset came from an ISA
>> - * hole. If they don't match, bugger.
>> - */
>> - if (memno == 0 ||
>> - (isa_hole >= 0 && pci_addr != 0 &&
>> - hose->pci_mem_offset == isa_mb))
>> - hose->pci_mem_offset = cpu_addr - pci_addr;
>> - else if (pci_addr != 0 &&
>> - hose->pci_mem_offset != cpu_addr - pci_addr) {
>> - printk(KERN_INFO
>> - " \\--> Skipped (offset mismatch) !\n");
>> - continue;
>> - }
>> -
>> - /* Build resource */
>> - res = &hose->mem_resources[memno++];
>> - res->flags = IORESOURCE_MEM;
>> - if (pci_space & 0x40000000)
>> - res->flags |= IORESOURCE_PREFETCH;
>> - res->start = cpu_addr;
>> - break;
>> - }
>> - if (res != NULL) {
>> - res->name = dev->full_name;
>> - res->end = res->start + size - 1;
>> - res->parent = NULL;
>> - res->sibling = NULL;
>> - res->child = NULL;
>> - }
>> - }
>> -
>> - /* If there's an ISA hole and the pci_mem_offset is -not- matching
>> - * the ISA hole offset, then we need to remove the ISA hole from
>> - * the resource list for that brige
>> - */
>> - if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
>> - unsigned int next = isa_hole + 1;
>> - printk(KERN_INFO " Removing ISA hole at 0x%016llx\n", isa_mb);
>> - if (next < memno)
>> - memmove(&hose->mem_resources[isa_hole],
>> - &hose->mem_resources[next],
>> - sizeof(struct resource) * (memno - next));
>> - hose->mem_resources[--memno].flags = 0;
>> - }
>> -}
>> -
>> /* Decide whether to display the domain number in /proc */
>> int pci_proc_domain(struct pci_bus *bus)
>> {
>> diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
>> index 13e37e2..1626172 100644
>> --- a/drivers/of/of_pci.c
>> +++ b/drivers/of/of_pci.c
>> @@ -4,6 +4,10 @@
>> #include <linux/of_pci.h>
>> #include <asm/prom.h>
>>
>> +#if defined(CONFIG_PPC32) || defined(CONFIG_PPC64) || defined(CONFIG_MICROBLAZE)
>> +#include <asm/pci-bridge.h>
>> +#endif
>> +
>> static inline int __of_pci_pci_compare(struct device_node *node,
>> unsigned int devfn)
>> {
>> @@ -40,3 +44,199 @@ struct device_node *of_pci_find_child_device(struct device_node *parent,
>> return NULL;
>> }
>> EXPORT_SYMBOL_GPL(of_pci_find_child_device);
>> +
>> +/**
>> + * pci_process_bridge_OF_ranges - Parse PCI bridge resources from device tree
>> + * @hose: newly allocated pci_controller to be setup
>> + * @dev: device node of the host bridge
>> + * @primary: set if primary bus (32 bits only, soon to be deprecated)
>> + *
>> + * This function will parse the "ranges" property of a PCI host bridge device
>> + * node and setup the resource mapping of a pci controller based on its
>> + * content.
>> + *
>> + * Life would be boring if it wasn't for a few issues that we have to deal
>> + * with here:
>> + *
>> + * - We can only cope with one IO space range and up to 3 Memory space
>> + * ranges. However, some machines (thanks Apple !) tend to split their
>> + * space into lots of small contiguous ranges. So we have to coalesce.
>> + *
>> + * - We can only cope with all memory ranges having the same offset
>> + * between CPU addresses and PCI addresses. Unfortunately, some bridges
>> + * are setup for a large 1:1 mapping along with a small "window" which
>> + * maps PCI address 0 to some arbitrary high address of the CPU space in
>> + * order to give access to the ISA memory hole.
>> + * The way out of here that I've chosen for now is to always set the
>> + * offset based on the first resource found, then override it if we
>> + * have a different offset and the previous was set by an ISA hole.
>> + *
>> + * - Some busses have IO space not starting at 0, which causes trouble with
>> + * the way we do our IO resource renumbering. The code somewhat deals with
>> + * it for 64 bits but I would expect problems on 32 bits.
>> + *
>> + * - Some 32 bits platforms such as 4xx can have physical space larger than
>> + * 32 bits so we need to use 64 bits values for the parsing
>> + */
>> +#if defined(CONFIG_PPC32) || defined(CONFIG_PPC64) || defined(CONFIG_MICROBLAZE)
>> +void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> + struct device_node *dev, int primary)
>> +{
>> + const u32 *ranges;
>> + int rlen;
>> + int pna = of_n_addr_cells(dev);
>> + int np = pna + 5;
>> + int memno = 0, isa_hole = -1;
>> + u32 pci_space;
>> + unsigned long long pci_addr, cpu_addr, pci_next, cpu_next, size;
>> + unsigned long long isa_mb = 0;
>> + struct resource *res;
>> +
>> + pr_info("PCI host bridge %s %s ranges:\n",
>> + dev->full_name, primary ? "(primary)" : "");
>> +
>> + /* Get ranges property */
>> + ranges = of_get_property(dev, "ranges", &rlen);
>> + if (ranges == NULL)
>> + return;
>> +
>> + /* Parse it */
>> + pr_debug("Parsing ranges property...\n");
>> + while ((rlen -= np * 4) >= 0) {
>> + /* Read next ranges element */
>> + pci_space = ranges[0];
>> + pci_addr = of_read_number(ranges + 1, 2);
>> + cpu_addr = of_translate_address(dev, ranges + 3);
>> + size = of_read_number(ranges + pna + 3, 2);
>> +
>> + pr_debug("pci_space: 0x%08x pci_addr:0x%016llx ",
>> + pci_space, pci_addr);
>> + pr_debug("cpu_addr:0x%016llx size:0x%016llx\n",
>> + cpu_addr, size);
>> +
>> + ranges += np;
>> +
>> + /* If we failed translation or got a zero-sized region
>> + * (some FW try to feed us with non sensical zero sized regions
>> + * such as power3 which look like some kind of attempt
>> + * at exposing the VGA memory hole)
>> + */
>> + if (cpu_addr == OF_BAD_ADDR || size == 0)
>> + continue;
>> +
>> + /* Now consume following elements while they are contiguous */
>> + for (; rlen >= np * sizeof(u32);
>> + ranges += np, rlen -= np * 4) {
>> + if (ranges[0] != pci_space)
>> + break;
>> + pci_next = of_read_number(ranges + 1, 2);
>> + cpu_next = of_translate_address(dev, ranges + 3);
>> + if (pci_next != pci_addr + size ||
>> + cpu_next != cpu_addr + size)
>> + break;
>> + size += of_read_number(ranges + pna + 3, 2);
>> + }
>> +
>> + /* Act based on address space type */
>> + res = NULL;
>> + switch ((pci_space >> 24) & 0x3) {
>> + case 1: /* PCI IO space */
>> + pr_info(" IO 0x%016llx..0x%016llx -> 0x%016llx\n",
>> + cpu_addr, cpu_addr + size - 1, pci_addr);
>> +
>> + /* We support only one IO range */
>> + if (hose->pci_io_size) {
>> + pr_info(" \\--> Skipped (too many) !\n");
>> + continue;
>> + }
>> +#if (!IS_ENABLED(CONFIG_64BIT))
>> + /* On 32 bits, limit I/O space to 16MB */
>> + if (size > 0x01000000)
>> + size = 0x01000000;
>> +
>> + /* 32 bits needs to map IOs here */
>> + hose->io_base_virt = ioremap(cpu_addr, size);
>> +
>> + /* Expect trouble if pci_addr is not 0 */
>> + if (primary)
>> + isa_io_base =
>> + (unsigned long)hose->io_base_virt;
>> +#endif /* !CONFIG_64BIT */
>> + /* pci_io_size and io_base_phys always represent IO
>> + * space starting at 0 so we factor in pci_addr
>> + */
>> + hose->pci_io_size = pci_addr + size;
>> + hose->io_base_phys = cpu_addr - pci_addr;
>> +
>> + /* Build resource */
>> + res = &hose->io_resource;
>> + res->flags = IORESOURCE_IO;
>> + res->start = pci_addr;
>> + break;
>> + case 2: /* PCI Memory space */
>> + case 3: /* PCI 64 bits Memory space */
>> + pr_info(" MEM 0x%016llx..0x%016llx -> 0x%016llx %s\n",
>> + cpu_addr, cpu_addr + size - 1, pci_addr,
>> + (pci_space & 0x40000000) ? "Prefetch" : "");
>> +
>> + /* We support only 3 memory ranges */
>> + if (memno >= 3) {
>> + pr_info(" \\--> Skipped (too many) !\n");
>> + continue;
>> + }
>> + /* Handles ISA memory hole space here */
>> + if (pci_addr == 0) {
>> + isa_mb = cpu_addr;
>> + isa_hole = memno;
>> + if (primary || isa_mem_base == 0)
>> + isa_mem_base = cpu_addr;
>> + hose->isa_mem_phys = cpu_addr;
>> + hose->isa_mem_size = size;
>> + }
>> +
>> + /* We get the PCI/Mem offset from the first range or
>> + * the, current one if the offset came from an ISA
>> + * hole. If they don't match, bugger.
>> + */
>> + if (memno == 0 ||
>> + (isa_hole >= 0 && pci_addr != 0 &&
>> + hose->pci_mem_offset == isa_mb))
>> + hose->pci_mem_offset = cpu_addr - pci_addr;
>> + else if (pci_addr != 0 &&
>> + hose->pci_mem_offset != cpu_addr - pci_addr) {
>> + pr_info(" \\--> Skipped (offset mismatch) !\n");
>> + continue;
>> + }
>> +
>> + /* Build resource */
>> + res = &hose->mem_resources[memno++];
>> + res->flags = IORESOURCE_MEM;
>> + if (pci_space & 0x40000000)
>> + res->flags |= IORESOURCE_PREFETCH;
>> + res->start = cpu_addr;
>> + break;
>> + }
>> + if (res != NULL) {
>> + res->name = dev->full_name;
>> + res->end = res->start + size - 1;
>> + res->parent = NULL;
>> + res->sibling = NULL;
>> + res->child = NULL;
>> + }
>> + }
>> +
>> + /* If there's an ISA hole and the pci_mem_offset is -not- matching
>> + * the ISA hole offset, then we need to remove the ISA hole from
>> + * the resource list for that brige
>> + */
>> + if (isa_hole >= 0 && hose->pci_mem_offset != isa_mb) {
>> + unsigned int next = isa_hole + 1;
>> + pr_info(" Removing ISA hole at 0x%016llx\n", isa_mb);
>> + if (next < memno)
>> + memmove(&hose->mem_resources[isa_hole],
>> + &hose->mem_resources[next],
>> + sizeof(struct resource) * (memno - next));
>> + hose->mem_resources[--memno].flags = 0;
>> + }
>> +}
>> +#endif
>> diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
>> index bb115de..33e8ead 100644
>> --- a/include/linux/of_pci.h
>> +++ b/include/linux/of_pci.h
>> @@ -11,4 +11,8 @@ struct device_node;
>> struct device_node *of_pci_find_child_device(struct device_node *parent,
>> unsigned int devfn);
>>
>> +struct pci_controller;
>> +void pci_process_bridge_OF_ranges(struct pci_controller *hose,
>> + struct device_node *dev, int primary);
>> +
>> #endif
>
>
>


--
Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID:
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel - Microblaze cpu - http://www.monstr.eu/fdt/
Maintainer of Linux kernel - Xilinx Zynq ARM architecture
Microblaze U-BOOT custodian and responsible for u-boot arm zynq platform

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